[oilpan] The Node hierarchy should have correct accept method chains

Source/core/html/HTMLDocument.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 64 matching lines @@
 
     void addExtraNamedItem(const AtomicString& name);
     void removeExtraNamedItem(const AtomicString& name);
     bool hasExtraNamedItem(AtomicStringImpl* name);
 
     static bool isCaseSensitiveAttribute(const QualifiedName&);
 
 protected:
     HTMLDocument(Frame*, const KURL&);
 
+    virtual void acceptHeapVisitor(Visitor*) const OVERRIDE;
+
 private:
     virtual PassRefPtr<Element> createElement(const AtomicString& tagName, ExceptionCode&);
 
     virtual bool isFrameSet() const;
     virtual PassRefPtr<DocumentParser> createParser();
 
     void addItemToMap(HashCountedSet<AtomicStringImpl*>&, const AtomicString&);
     void removeItemFromMap(HashCountedSet<AtomicStringImpl*>&, const AtomicString&);
 
     HashCountedSet<AtomicStringImpl*> m_namedItemCounts;
@@ skipping 43 matching lines @@
 {
     return toHTMLDocument(Handle<const Document>(document));
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toHTMLDocument(const HTMLDocument*);
 
 } // namespace WebCore
 
 #endif // HTMLDocument_h